Happy First Day of Spring! or Vernal Equinox, a “Quarter Day” of the Earth’s revolution around the sun. The day and night cycle is close to equal – about 12 hours and 10 minutes of sunlight here in Western Pennsylvania today. Today is halfway between the [approximately] longest day of the year in June and the shortest day in December. Flora and fauna are waking from their winter dormancy.
During the Equinox, the Sun’s Ecliptic Pathway crosses the Celestial Equator, as per the Glossary of Astronomical Phenomena:
Vernal Equinox – The intersection of the celestial equator and the sun’s ecliptic pathway in it’s northern ascent towards the tropic of Cancer. At this time, the Earth’s axial tilt is facing neither toward nor away from the sun, and there is approximately 12 hours of daylight and nighttime. This marks the beginning of the spring season in the northern hemisphere.
As demonstrated below, the Sun’s pathway across the Earth’s sky goes higher, or closer to the Zenith, as the wheel the year gets closer to the Summer Solstice in June. This is known as the Tropic of Cancer. During the northern summer months, the Sun’s energy both is directed more towards the northern hemisphere and present for a longer period of time, the longer day.
Right now, night is receding and making way for longer, warmer days. It is time to get outside and enjoy it!